From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f69.google.com (mail-it0-f69.google.com [209.85.214.69]) by kanga.kvack.org (Postfix) with ESMTP id 26C466B0069 for ; Mon, 20 Nov 2017 07:16:18 -0500 (EST) Received: by mail-it0-f69.google.com with SMTP id c18so4842210itd.8 for ; Mon, 20 Nov 2017 04:16:18 -0800 (PST) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id x19sor4426548ioe.291.2017.11.20.04.16.16 for (Google Transport Security); Mon, 20 Nov 2017 04:16:16 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20171120120422.a6r4govoyxjbgp7w@dhcp22.suse.cz> References: <1510888199-5886-1-git-send-email-laoar.shao@gmail.com> <20171117155509.GA920@castle> <20171117164531.GA23745@castle> <20171120120422.a6r4govoyxjbgp7w@dhcp22.suse.cz> From: Yafang Shao Date: Mon, 20 Nov 2017 20:16:15 +0800 Message-ID: Subject: Re: [PATCH] mm/shmem: set default tmpfs size according to memcg limit Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Shakeel Butt , Roman Gushchin , Andrew Morton , Johannes Weiner , Vladimir Davydov , Tejun Heo , khlebnikov@yandex-team.ru, mka@chromium.org, Hugh Dickins , Cgroups , Linux MM , LKML 2017-11-20 20:04 GMT+08:00 Michal Hocko : > On Fri 17-11-17 09:49:54, Shakeel Butt wrote: >> On Fri, Nov 17, 2017 at 9:41 AM, Yafang Shao wrote: > [...] >> > Of couse that is the best way. >> > But we can not ensue all applications will do it. >> > That's why I introduce a proper defalut value for them. >> > >> >> I think we disagree on the how to get proper default value. Unless you >> can restrict that all the memory allocated for a tmpfs mount will be >> charged to a specific memcg, you should not just pick limit of the >> memcg of the process mounting the tmpfs to set the default of tmpfs >> mount. If you can restrict tmpfs charging to a specific memcg then the >> limit of that memcg should be used to set the default of the tmpfs >> mount. However this feature is not present in the upstream kernel at >> the moment (We have this feature in our local kernel and I am planning >> to upstream that). > > I think the whole problem is that containers pretend to be independent > while they share a non-reclaimable resource. Fix this and you will not > have a problem. I am afraid that the only real fix is to make tmpfs > private per container instance and that is something you can easily > achieve in the userspace. > Agree with you. Introduce tmpfs stat in memory cgroup, something like memory.tmpfs.limit memory.tmpfs.usage IMHO this is the best solution. Thanks Yafang -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org